When I write this, Rails already release RC1 version and I want to try it because all seems near production ready, only 4 issues on github when they announce Beta 4 release.

Here are the steps to install Rails 5 (RC1) for me:

• rvm install 2.3.1
• rvm use ruby-2.3.1@rails5.0 –create
  (create rvm gemset for new rails version using latest ruby 2.3.1)
• gem install rails –version=5.0.0.rc1 (replace with 5.0.0 if rails already release final 5.0.0 version

Then check the rails version:

• rails -v

It will show you “Rails 5.0.0.rc1” on console